I remember that in the late seventies some of the cars that were sold in the US got over forty miles per gallon (Volkswagon Rabbit, for example). Why are there no equivalent 45 mpg cars now? (I am talking about standard gasoline-powered cars mass-marketed in the US and made by the major automobile manufacturers, not hybrids, etc.) I assume it is because the pollution-control equipment now required on new vehicles robs much of the engine power. Has anyone done any calculations to see how much additional gasoline is used to make up for the loss of power caused by this equipment?

I think about the same thing all the time. My '05 Ford Superduty gets 16MPG unloaded on the highway, whereas I had a '97 that got 22MPG. That is a 30% reduction in fuel economy. I'm thinking the addition of an exhaust gas recirculator and catalyst could be a culprit. EGR sounds like a particularly bad idea on turbo vehicles because your "recompressing" oxygen deprived air (wasting energy) and diluting the oxygen within every charge of fresh air.

Now there might be less unburned hydrocarbons by volume within the exhaust gases, but how much has the total volume increased? Could the higher volume of "cleaner" exhaust gasses be more harmful than a lower volume of "dirty" emissions? It seems to me that EGR could be a way to cheat the system in meeting the EPM's poorly written requirements through diluting the exhaust gasses with more air. Mixing oxygen deprived air with the fresh air will require more air in the A/F ratio. Even if the unburned hydrocarbon level is "unchanged" the tailpipe sniffer will read lower levels. At any rate, were all burning up the fuel supply faster for sure.

Emissions should be measured in units of mass/time not mass/volume. I need to stop thinking about this stuff and how humanity __ ___ ______ ___ ___ ___ _____ !

Surely we can't be the only people who have wondered about the increased fuel consumption caused by pollution controls. I'll bet someone, somewhere has done the math on it.

Heres some things that will likely make you even more upset!

An air fuel ratio of around 12.9:1 will actually give you more power and better mileage than the 14.7:1 ratio that got shoved down our throats to dilute the exhaust gases and meet the stoichiometric air fuel ratio as calculated by some chemist. The most efficient air fuel ratio is often considerably different simply because real world gasoline is not the high quality high energy stuff the labs based the air fuel ratio on. By putting a belt driven air blower on your engine and blowing clean fresh air into the exhaust as a bulk dilutant the parts per million numbers will be greatly reduced. External dilution of exhaust gas after combustion works way better and saves fuel. Regardless of how you burn fuel it creates the same mass of by products. Chemical and physics fact! 100 ppm diluted with 10x air will magically become 10ppm! Put a big enough air blower on a burning tractor tire and it too will pass an emissions test! Exhaust emissions controls are a fake! All they do is make you burn more fuel to do the same work load. You have actually put more bad pollutants into the air by having an emissions compliant vehicle! It just tests as less be cause the pollutants are diluted down more. The actual total volume made per unit of fuel burned is the same. Its a simple chemistry fact! Any high school level chemistry teacher can tell you this too!

I drive semi in the fall for harvest and heres a bit of information thats really a WTF point. Talk to any truck driver to confirm this too. I am not lying! The truck I drive is seasonally licenced for 90000 pounds gross weight. It spends all day crawling around fields fully loaded. I have to do the fueling and general maintenance on it too. That truck, all 90000 pounds of it, gets 5 - 6 MPG.

My 1999 Ford F250 all 6500 pounds of it empty strait highway driving only gets double what the semi does. WTF? nearly 14 times lighter and far more aerodynamic but only double the mileage.

If I put my flatbed trailer on it and have it loaded I get the same mileage as the semi does. 5 times lighter and the same mileage WTF?